The Power of Habit – Why We Do What We Do in Life and Business

advanced regions, such as the prefrontal cortex. Sleepwalkers have been known to boil water and make tea. One operated a motorboat. Another turned on an electric saw and started feeding in pieces of wood before going back to bed. But in general, sleepwalkers will not do things that are dangerous to themselves or others. Even asleep, there’s an instinct to avoid peril.

However, as scientists have examined the brains of sleepwalkers, they’ve found a distinction between sleepwalking-in which people might leave their beds and start acting out their dreams or other mild impulses-and something called sleep terrors. [262] When a sleep terror occurs, the activity inside people’s brains is markedly different from when they are awake, semi-conscious, or even sleepwalking. People in the midst of sleep terrors seem to be in the grip of terrible anxieties, but are not dreaming in the normal sense of the word. Their brains shut down except for the most primitive neurological regions, which include what are known as “central pattern generators.” These areas of the brain are the same ones studied by Dr. Larry Squire and the scientists at MIT, who found the neurological machinery of the habit loop. To a neurologist, in fact, a brain experiencing a sleep terror looks very similar to a brain following a habit.

The behaviors of people in the grip of sleep terrors are habits, though of the most primal kind. The “central pattern generators” at work during a sleep terror are where such behavioral patterns as walking, breathing, flinching from a loud noise, or fighting an attacker come from. We don’t usually think about these behaviors as habits, but that’s what they are: automatic behaviors so ingrained in our neurology that, studies show, they can occur with almost no input from the higher regions of the brain.

However, these habits, when they occur during sleep terrors, are different in one critical respect: Because sleep deactivates the prefrontal cortex and other high cognition areas, when a sleep terror habit is triggered, there is no possibility of conscious intervention. If the fight-or-flight habit is cued by a sleep terror, there is no chance that someone can override it through logic or reason.

“People with sleep terrors aren’t dreaming in the normal sense,” said Mahowald, the neurologist. “There’s no complex plots like you and I remember from a nightmare. If they remember anything afterward, it’s just an image or emotions-impending doom, horrible fear, the need to defend themselves or someone else.

“Those emotions are really powerful, though. They are some of the most basic cues for all kinds of behaviors we’ve learned throughout our lives. Responding to a threat by running away or defending ourselves is something everyone has practiced since they were babies. And when those emotions occur, and there’s no chance for the higher brain to put things in context, we react the way our deepest habits tell us to. [263] We run or fight or follow whatever behavioral pattern is easiest for our brains to latch on to.”

When someone in the midst of a sleep terror starts feeling threatened or sexually aroused-two of the most common sleep terror experiences-they react by following the habits associated with those stimuli. People experiencing sleep terrors have jumped off of tall roofs because they believed they were fleeing from attackers. They have killed their own babies because, they believed, they were fighting wild animals. They have raped their spouses, even as their victims begged them to stop, because once the sleepers’ arousal began, they followed the ingrained habit to satisfy the urge. Sleepwalking seems to allow some choice, some participation by our higher brains that tell us to stay away from the edge of the roof. Someone in the grip of a sleep terror, however, simply follows the habit loop no matter where it leads.

Some scientists suspect sleep terrors might be genetic; others say diseases such as Parkinson’s make them more likely. Their causes aren’t well understood, but for a number of people, sleep terrors involve violent impulses. “Violence related to sleep terrors appears to be a reaction to a concrete, frightening image that the individual can subsequently describe,” a group of Swiss researchers wrote in 2009. Among people suffering one type of sleep dysfunction, “attempted assault of sleep partners has been reported to occur in 64% of cases, with injuries in 3%.” [264]

In both the United States and the United Kingdom, there is a history of murderers arguing that sleep terrors caused them to commit crimes they would have never consciously carried out. [265] [266] Four years before Thomas was arrested, for instance, a man named Jules Lowe was found not guilty of murdering his eighty-three-year-old father after claiming that the attack occurred during a sleep terror. [267] Prosecutors argued it was “far-fetched in the extreme” to believe that Lowe was asleep while he punched, kicked, and stamped his father for more than twenty minutes, leaving him with over ninety injuries. The jury disagreed and set him free. In September 2008, thirty-three-year-old Donna Sheppard-Saunders nearly suffocated her mother by holding a pillow over her face for thirty seconds. She was later acquitted of attempted murder by arguing that she had acted while asleep. [268] In 2009, a British soldier admitted to raping a teenage girl, but said he was asleep and unconscious while he undressed himself, pulled down her pants, and began having sex. When he woke, mid-rape, he apologized and called the police. “I’ve just sort of committed a crime,” he told the emergency operator. “I honestly don’t know what happened. I woke up on top of her.” He had a history of suffering from sleep terrors and was found not guilty. [269] More than 150 murderers and rapists have escaped punishment in the past century using the automatism defense. Judges and juries, acting on behalf of society, have said that since the criminals didn’t choose to commit their crimes-since they didn’t consciously participate in the violence-they shouldn’t bear the blame.

For Brian Thomas, it also looked like a situation where a sleep disorder, rather than a murderous impulse, was at fault. “I’ll never forgive myself, ever,” he told one of the prosecutors. “Why did I do it?” [270]

After Dr. Idzikowski, the sleep specialist, observed Thomas in his laboratory, he submitted his findings: Thomas was asleep when he killed his wife. He hadn’t consciously committed a crime.

As the trial started, prosecutors presented their evidence to the jury. Thomas had admitted to murdering his wife, they told jurors. He knew he had a history of sleepwalking. His failure to take precautions while on vacation, they said, made him responsible for his crime.

But as arguments proceeded, it became clear prosecutors were fighting an uphill battle. Thomas’s lawyer argued that his client hadn’t meant to kill his wife-in fact, he wasn’t even in control of his own actions that night. Instead, he was reacting automatically to a perceived threat. He was following a habit almost as old as our species: the instinct to fight an attacker and protect a loved one. Once the most primitive parts of his brain were exposed to a cue-someone strangling his wife-his habit took over and he fought back, with no chance of his higher cognition interceding. Thomas was guilty of nothing more than being human, the lawyer argued, and reacting in the way his neurology-and most primitive habits-forced him to behave.

Even the prosecution’s own witnesses seemed to bolster the defense. Though Thomas had known he was capable of sleepwalking, the prosecution’s own psychiatrists said, there was nothing to suggest to him that it was therefore foreseeable he might kill. He had never attacked anyone in his sleep before. He had never previously harmed his wife.

When the prosecution’s chief psychiatrist took the stand, Thomas’s lawyer began his cross-examination.

Did it seem fair that Thomas should be found guilty for an act he could not know was going to occur?

In her opinion, said Dr. Caroline Jacob, Thomas could not have reasonably anticipated his crime. And if he was convicted and sentenced to Broadmoor Hospital, where some of Britain’s most dangerous and mentally ill criminals were housed, well, “he does not belong there.”

The next morning, the head prosecutor addressed the jury.

“At the time of the killing the defendant was asleep and his mind had no control over what his body was doing,” he said. [271] “We have reached the conclusion that the public interest would no longer be served by continuing to seek a special verdict from you. We therefore offer no further evidence and invite you to return a straight not guilty verdict.” [272] The jury did so.

Before Thomas was set free, the judge told him, “You are a decent man and a devoted husband. I strongly suspect you may well be feeling a sense of guilt. In the eyes of the law you bear no responsibility. [273] You are discharged.”

It seems like a fair outcome. After all, Thomas was obviously devastated by his crime. He had no idea what he